1. Field of the Invention
The present invention relates to a variable-position operation device which causes a plurality of light-emitting elements to selectively emit light in accordance with a shift position of a variable-position operation member, and guides the emitted light to a display part of the variable-position operation member.
2. Description of Related Art
For example, digital cameras of recent years are typically provided with a rotational operation dial (rotational operation member) which selects various photographic modes and operations, and peripheral display parts of the rotational operation dial are made to selectively emit light in order to further improve the visual confirmation ability thereof (Japanese Unexamined Patent Publication Nos. H11-219639 and 2001-005075).
In such a rotational operation dial, in order to detect the rotational position of the rotational operation dial, a brush is fixed to the rotational operation dial, and a circuit board provided with lands, to which the brush comes in sliding contact with, is fixed onto the body of the device (digital camera). Furthermore, a plurality of light-emitting elements are provided on aback surface (inner surface) of the rotational operation dial, in which at least the display parts thereof are transparent; these light-emitting elements are selectively made to emit light.
In the related art, it is technical common sense to provide lands, to which the brush is in slidable contact, and light-emitting elements on the same surface (side) of the same board (circuit board). However, according to the inventor of the present invention, if the space between the lands and the light-emitting elements (surface mounted LEDs), which are soldered onto the same surface of the same board, is narrow, there is a risk of the melted solder short-circuiting between the terminals of the light-emitting elements and the lands, and there is a risk of the contacting surfaces between the lands and the brush becoming contaminated. Accordingly, a sufficiently wide space must be provided between the lands and the light-emitting elements, which hinders miniaturization (reduction in the diameter) of the rotational operation dial. In particular, in a configuration in which a push-button switch is provided at an inner peripheral side (inner radial position) of the rotational operation dial, a switch element(s) for the push-button switch must be provided on the same surface on which the lands are provided and at the inner peripheral side (inner radial position) of the lands, so that there is a risk of the lands and the terminals of the switch element short circuiting caused by soldering. Accordingly, a sufficient amount of space must be obtained between the lands, the light-emitting elements and the switch element(s), causing difficulties in reducing (miniaturizing) the mounting area and the surface area of the board (circuit board), thereby causing difficulties in miniaturizing (miniaturizing the diameter of) the rotational operation dial (rotational operation member).